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Accuracy of dynamic orbit determination using rebuilt space-borne\nGPS pseudo-range measurements from real-time navigation solutions
星载GPS 伪距观测量重建及定轨精度分析

PENG Dongju,HU Xiaogong,WU Bin,
彭冬菊
,胡小工,吴斌

遥感学报 , 2010,
Abstract: The method to rebuild space-borne pseudo-range measurements from real-time position data is discussed first in this paper. And then, the accuracy of dynamic orbit determination using rebuilt pseudo-range measurements and precise GPS ephemeris is analyzed in detail. Data from GRACE-A satellite from March 1 to 14 in 2008 is processed for this purpose. Research results show that the accuracy of real-time single point positioning using C/A code pseudo-range measurements and GPS broadcast ephemeris is about 15m, and the accuracy of dynamic orbit determination in post-processing mode is about 2m. It is demonstrated that dynamic orbit determination using rebuilt pseudo-range measurements in post-processing mode can not only significantly improve the position accuracy of real-time navigation solutions, but also provide consecutive satellite orbits.
基于伪距和观测量的地球同步卫星动力学定轨研究  [PDF]
贾小林,焦文海,王刚,吴显兵,陈金平
空间科学学报 , 2004,
Abstract: 利用伪距和观测量对同步卫星进行了动力学定轨的研究,给出了伪距和观测量的测量方程和修正方法,采用国内4个监测站的模拟数据进行了仿真计算.结果表明,采用7天弧长伪距和数据进行轨道改进及轨道外推的精度,与5天弧长数据的计算结果相当,但远优于3天数据的计算结果.在观测随机误差为3m时,7天弧长数据定轨精度约为5m,预报7天径向精度优于20m.
星载GPS伪距多路径误差与观测噪声对自主定轨的影响分析
Impact of Multipath Error and Noise of Space-Borne GPS Code Measurements on Real-Time Onboard Orbit Determination
 [PDF]

龚学文, 王甫红
GONG Xuewen
, WANG Fuhong

- , 2018, DOI: 10.13203/j.whugis20160223
Abstract: 对搭载美国BlackJack接收机的CHAMP/GRACE-A/Jason-2卫星和搭载国产接收机的HY2A/ZY3/TH1卫星的星载GPS数据的伪距多路径误差与观测噪声进行了研究,重点分析了国产接收机伪距多路径误差的变化特性,并研究了多路径误差与观测噪声对星载GPS自主定轨的影响。结果表明:国产接收机的C/A码与P1码伪距观测精度要整体差于美国的BlackJack接收机,而P2码伪距观测精度要整体优于BlackJack接收机;国产接收机P1码伪距受多路径效应影响较大,其多路径误差随高度角减小存在单调递增的变化趋势,其中HY2A、ZY3与TH1卫星的多路径误差最大分别可达3.6 m、1.8 m与0.7 m;这种单调递增变化的多路径误差会导致星载GPS自主定轨位置结果在径向与切向产生系统性偏差
逆极限空间的逐点伪轨跟踪性  [PDF]
吴志湖,陈尔明
华侨大学学报(自然科学版) , 2009, DOI: 10.11830/ISSN.1000-5013.2009.05.0593
Abstract: 证明对于由{Xi,φi,fi}i∞=1生成的逆极限系统{X∞,f∞},如果每个fi具有逐点伪轨跟踪性,则诱导映射f∞也具有逐点伪轨跟踪性.举例证明,它的逆命题不成立.
非游荡算子的伪轨跟踪性质的推广及应用  [PDF]
王明刚,许华
四川师范大学学报(自然科学版) , 2011,
Abstract: 伪轨跟踪性质是动力系统中的重要概念之一,它与系统的稳定性以及混沌都有密切的联系.然而伪轨的概念仅仅局限在有限维紧的度量空间中,将这一工作发展到无穷维可分Banach空间上的线性算子的研究之中,在无穷维可分Banach空间中引进了α伪轨,定义了非游荡常数,给出了在Banach序列空间及其具有物理背景的空间中非游荡算子的α伪轨的例子,运用泛函分析的方法对非游荡算子的伪轨跟踪性质进行了推广,最后利用此性质得到了几个重要的结论,推进和完善了对非游荡算子性质的研究.
伪随机脉冲先验值对低轨卫星简化动力学定轨精度的影响
Impact of Pseudo-Stochastic Pulse Priors on LEO Reduced-Dynamic Orbit Accuracy
 [PDF]

张兵兵, 王正涛, 冯建迪, 邱耀东
ZHANG Bingbing
, WANG Zhengtao, FENG Jiandi, QIU Yaodong

- , 2018, DOI: 10.13203/j.whugis20160168
Abstract: 低轨卫星简化动力学定轨中引入伪随机脉冲可有效提高定轨精度,但伪随机脉冲先验值(时间间隔、先验标准差)会影响伪随机脉冲估值大小,进而影响定轨精度。基于GRACE(Gravity Recovery and Climate Experiment)卫星轨道分析伪随机脉冲先验值对单天解简化动力学定轨精度的影响,实验表明,时间间隔从240 min减至6 min,先验标准差从1×10-4mm/s增至1×10-1mm/s,伪随机脉冲总的估值大小由1×10-2mm/s增至1×101mm/s,定轨精度从几十cm提高到2 cm;当先验标准差大于1×10-1mm/s,继续增加先验标准差,伪随机脉冲估值不变,定轨精度不再提高。因此,对于单天解轨道,时间间隔减小至6 min,先验标准差增至1×10-1mm/s,伪随机脉冲估值增大,定轨精度提高;继续增大先验标准差,伪随机脉冲估值不变,定轨精度不再提高。利用不同高度的Swarm卫星验证了该结论的有效性
星载GNSS低轨卫星精密定轨快速解算方法  [PDF]
田英国,郝金明,刘伟平,于合理,王鸿,杨剑伟
大地测量与地球动力学 , 2014,
Abstract: ?针对星载GNSS低轨卫星精密定轨过程中需估计大量的钟差参数、模糊度参数及伪随机轨道参数,导致求解耗时较长的问题,利用参数预消除的原理分别对不同类型的待估参数进行预消除从而提高计算效率,并对伪随机轨道参数难以直接预消除问题进行分析,给出了利用轨道参数在子区间Ii-1与Ii间的递推关系进行参数预消除的方法。最后通过实验验证了该方法的有效性。
基于转发式的北斗卫星导航系统地球静止轨道卫星精密定轨试验  [PDF]
雷辉,李志刚,杨旭海,武文俊成璇,冯初刚
测绘学报 , 2011,
Abstract: GEO卫星在COMPASS卫星导航中具有特别重要的作用,除了利用导航系统自身的伪距相位以外,利用其他的测轨系统对其进行精密定轨有着重要的意义。利用国家授时中心的转发式测轨网对COMPASS的GEO卫星进行观测,获取转发式测轨数据,本文利用该数据对COMPASS的GEO卫星进行精密定轨分析。分别从观测数据的观测精度,定轨残差以及轨道重叠误差等方面分析了GEO卫星的定轨精度。
Intrusion Detection System Based on MAS with Rebuilt Function
基于具有重构功能MAS的入侵检测系统*

JING Xu,HAN Yong-guo,FAN Tai-hua,
景旭
,韩永国,范太华

计算机应用研究 , 2005,
Abstract: Facing to the disadvantage of the intrusion detection system,an IDS based on MAS which has the rebuilt function is proposed.At the same time the systemic structure of the intrusion detection system based on the MAS with rebuilt function, the function of each Agent and the procedure of the MAS in the system are introduced in detail.
How can micelle systems be rebuilt by a heating process?
Silva-Filho MA, Siqueira SDVS, Freire LB, Araújo IB, Silva KGH, Medeiros AC, Araújo-Filho I, Oliveira AG, Egito EST
International Journal of Nanomedicine , 2012, DOI: http://dx.doi.org/10.2147/IJN.S25761
Abstract: w can micelle systems be rebuilt by a heating process? Original Research (1924) Total Article Views Authors: Silva-Filho MA, Siqueira SDVS, Freire LB, Araújo IB, Silva KGH, Medeiros AC, Araújo-Filho I, Oliveira AG, Egito EST Published Date January 2012 Volume 2012:7 Pages 141 - 150 DOI: http://dx.doi.org/10.2147/IJN.S25761 Received: 02 September 2011 Accepted: 10 October 2011 Published: 12 January 2012 Miguel Adelino da Silva-Filho1, Scheyla Daniela Vieira da Silva Siqueira1, Larissa Bandeira Freire1, Ivonete Batista de Araújo2, Káttya Gyselle de Holanda e Silva2, Aldo da Cunha Medeiros3, Irami Araújo-Filho3, Anselmo Gomes de Oliveira4, Eryvaldo Sócrates Tabosa do Egito2 1Dispersed Systems Laboratory, Federal University of Rio Grande do Norte (UFRN), Natal, Rio Grande do Norte, Brazil; 2Department of Pharmacy, UFRN, Natal, Rio Grande do Norte, Brazil; 3Department of Experimental Surgery, UFRN, Natal, Rio Grande do Norte, Brazil; 4Department of Drugs and Medicines, College of Pharmaceutical Sciences (UNESP), Araraquara, S o Paulo, Brazil Abstract: The aim of this work was to evaluate how an aqueous micellar system containing Amphotericin B (AmB) and sodium deoxycholate (DOC) can be rebuilt after heating treatment. Also, a review of the literature on the physicochemical and biological properties of this new system was conducted. Heated (AmB-DOC-H) and unheated (AmB-DOC) micelles were then diluted at four different concentrations (50 mg · L-1, 5 mg · L-1, 0.5 mg · L-1, and 0.05 mg · L-1) to perform physicochemical studies and a pharmacotoxicity assay, in which two cell models were used for the in vitro experiments: red blood cells (RBC) from human donors and Candida parapsilosis (Cp). While potassium (K+) and hemoglobin leakage from RBC were the parameters used to evaluate acute and chronic toxicity, respectively, the efficacy of AmB-DOC and AmB-DOC-H were assessed by K+ leakage and cell survival rate from Cp. The spectral study revealed a slight change in the AmB-DOC aggregate peak from 327 nm to 323 nm, which is the peak for AmB-DOC-H. Although AmB-DOC and AmB-DOC-H exhibited different behavior for hemoglobin leakage, AmB-DOC produced higher leakage than AmB-DOC-H at high concentrations (from 5 mg ·L-1). For K+ leakage, both AmB-DOC and AmB-DOC-H showed a similar profile for both cell models, RBC and Cp (P < 0.05). AmB-DOC-H and AmB-DOC also revealed a similar profile of activity against Cp with an equivalent survival rate. In short, AmB-DOC-H showed much less toxicity than AmB-DOC, but remained as active as AmB-DOC against fungal cells. The results highlight the importance of this new procedure as a simple, inexpensive, and safe way to produce a new kind of micelle system for the treatment of systemic fungal infections.
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